Final answer:
Sardines are the best source of omega-3 fatty acids among the provided options, offering high levels of EPA and DHA which are beneficial for heart and brain health.
Step-by-step explanation:
The best source of omega-3 fatty acids among the options provided is D. Sardines. Omega-3 fatty acids, which are polyunsaturated fats, are crucial for heart health, reducing inflammation, and supporting brain function and development. While olive oil and avocado contain some beneficial fats, they are not rich sources of omega-3s. Shrimp does contain some omega-3s, but sardines are a more concentrated source. In fact, cold-water fatty fish such as sardines are especially high in the long-chain omega-3 fatty acids EPA and DHA, which are linked to a lower risk of heart disease and are important for brain health.